SUPPLEMENTAL CONDENSED CONSOLIDATING FINANCIAL INFORMATION - Statement of Comprehensive Income (Loss) (Details) - USD ($) $ in Thousands	3 Months Ended
	Jun. 30, 2018	Jun. 30, 2017
Condensed Financial Statements, Captions [Line Items]
Net income (loss)	$ (32,041)	$ (55,746)
Currency translation adjustments	(29,033)	9,760
Unrealized gain on cash flow hedges	1,348	0
Total comprehensive loss	(59,726)	(45,986)
Net (income) loss attributable to noncontrolling interests	(67)	471
Currency translation adjustments attributable to noncontrolling interests	(139)	310
Total comprehensive (income) loss attributable to noncontrolling interests	(206)	781
Total comprehensive loss attributable to Bristow Group	(59,932)	(45,205)
Eliminations
Condensed Financial Statements, Captions [Line Items]
Net income (loss)	7,309	20,645
Currency translation adjustments	53,655	(4,930)
Unrealized gain on cash flow hedges	0
Total comprehensive loss	60,964	15,715
Net (income) loss attributable to noncontrolling interests	0	0
Currency translation adjustments attributable to noncontrolling interests	0	0
Total comprehensive (income) loss attributable to noncontrolling interests	0	0
Total comprehensive loss attributable to Bristow Group	60,964	15,715
Parent Company Only
Condensed Financial Statements, Captions [Line Items]
Net income (loss)	(32,093)	(55,264)
Currency translation adjustments	0	0
Unrealized gain on cash flow hedges	0
Total comprehensive loss	(32,093)	(55,264)
Net (income) loss attributable to noncontrolling interests	(15)	(11)
Currency translation adjustments attributable to noncontrolling interests	0	0
Total comprehensive (income) loss attributable to noncontrolling interests	(15)	(11)
Total comprehensive loss attributable to Bristow Group	(32,108)	(55,275)
Guarantor Subsidiaries
Condensed Financial Statements, Captions [Line Items]
Net income (loss)	(9,266)	(3,686)
Currency translation adjustments	(886)	338
Unrealized gain on cash flow hedges	0
Total comprehensive loss	(10,152)	(3,348)
Net (income) loss attributable to noncontrolling interests	0	0
Currency translation adjustments attributable to noncontrolling interests	0	0
Total comprehensive (income) loss attributable to noncontrolling interests	0	0
Total comprehensive loss attributable to Bristow Group	(10,152)	(3,348)
Non- Guarantor Subsidiaries
Condensed Financial Statements, Captions [Line Items]
Net income (loss)	2,009	(17,441)
Currency translation adjustments	(81,802)	14,352
Unrealized gain on cash flow hedges	1,348
Total comprehensive loss	(78,445)	(3,089)
Net (income) loss attributable to noncontrolling interests	(52)	482
Currency translation adjustments attributable to noncontrolling interests	(139)	310
Total comprehensive (income) loss attributable to noncontrolling interests	(191)	792
Total comprehensive loss attributable to Bristow Group	$ (78,636)	$ (2,297)